////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2011-2021 The Octave Project Developers
//
// See the file COPYRIGHT.md in the top-level directory of this
// distribution or <https://octave.org/copyright/>.
//
// This file is part of Octave.
//
// Octave is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Octave is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Octave; see the file COPYING.  If not, see
// <https://www.gnu.org/licenses/>.
//
////////////////////////////////////////////////////////////////////////

#if ! defined (octave_Canvas_h)
#define octave_Canvas_h 1

#include <QObject>
#include <QPoint>

#include "event-manager.h"
#include "graphics.h"

#include "Figure.h"

class QKeyEvent;
class QMouseEvent;
class QWheelEvent;
class QWidget;

class octave_value_list;

namespace octave
{
  class base_qobject;
  class interpreter;
}

namespace octave
{

  class Canvas : public QObject
  {
    Q_OBJECT

  public:
    enum EventMask
    {
      KeyPress   = 0x01,
      KeyRelease = 0x02
    };

  public:
    virtual ~Canvas (void) = default;

    void redraw (bool sync = false);
    void blockRedraw (bool block = true);

    void print (const QString& file_cmd, const QString& term)
    {
      do_print (file_cmd, term, m_handle);
    }

    void addEventMask (int m) { m_eventMask |= m; }
    void clearEventMask (int m) { m_eventMask &= (~m); }
    void setEventMask (int m) { m_eventMask = m; }

    void setCursor (MouseMode mode, std::string fallback,
                    QImage cdata, Matrix hotspot);

    virtual QWidget * qWidget (void) = 0;

    static Canvas *
    create (octave::base_qobject& oct_qobj, octave::interpreter& interp,
            const graphics_handle& handle, QWidget *parent,
            const std::string& name);

    virtual uint8NDArray getPixels (void) { return do_getPixels (m_handle); };

  signals:

    void interpreter_event (const octave::fcn_callback& fcn);
    void interpreter_event (const octave::meth_callback& meth);

    void gh_callback_event (const graphics_handle& h, const std::string& name);

    void gh_callback_event (const graphics_handle& h, const std::string& name,
                            const octave_value& data);

    void gh_set_event (const graphics_handle& h, const std::string& name,
                       const octave_value& value);

    void gh_set_event (const graphics_handle& h, const std::string& name,
                       const octave_value& value, bool notify_toolkit);

    void gh_set_event (const graphics_handle& h, const std::string& name,
                       const octave_value& value, bool notify_toolkit,
                       bool redraw_figure);
  protected:
    virtual void draw (const graphics_handle& handle) = 0;
    virtual void drawZoomBox (const QPoint& p1, const QPoint& p2) = 0;
    virtual void resize (int x, int y, int width, int height) = 0;
    virtual graphics_object selectFromAxes (const graphics_object& ax,
                                            const QPoint& pt) = 0;
    virtual uint8NDArray do_getPixels (const graphics_handle& handle) = 0;
    virtual void do_print (const QString& file_cmd, const QString& term,
                           const graphics_handle& handle) = 0;

  protected:
    Canvas (octave::base_qobject& oct_qobj, octave::interpreter& interp,
            const graphics_handle& handle)
      : m_octave_qobj (oct_qobj),
        m_interpreter (interp),
        m_handle (handle),
        m_redrawBlocked (false),
        m_mouseMode (NoMode),
        m_clickMode (false),
        m_eventMask (0),
        m_rectMode (false)
    { }

    void canvasToggleAxes (const graphics_handle& handle);
    void canvasToggleGrid (const graphics_handle& handle);
    void canvasAutoAxes (const graphics_handle& handle);
    void canvasPaintEvent (void);
    void canvasMouseDoubleClickEvent (QMouseEvent *event);
    void canvasMouseMoveEvent (QMouseEvent *event);
    void canvasMousePressEvent (QMouseEvent *event);
    void canvasMouseReleaseEvent (QMouseEvent *event);
    void canvasWheelEvent (QWheelEvent *event);
    bool canvasKeyPressEvent (QKeyEvent *event);
    bool canvasKeyReleaseEvent (QKeyEvent *event);

    void updateCurrentPoint (const graphics_object& fig,
                             const graphics_object& obj, QMouseEvent *event);
    void updateCurrentPoint (const graphics_object& fig,
                             const graphics_object& obj);

    void select_object (graphics_object obj, QMouseEvent *event,
                        graphics_object& currentObj, graphics_object& axesObj,
                        bool axes_only = false,
                        std::vector<std::string> omit = std::vector<std::string> ());

  protected:
    octave::base_qobject& m_octave_qobj;
    octave::interpreter& m_interpreter;

  private:

    QCursor make_cursor (const QString& name, int hot_x  = -1, int hot_y = -1);

    graphics_handle m_handle;
    bool m_redrawBlocked;
    MouseMode m_mouseMode;
    bool m_clickMode;              // True: ZoomIn, False: ZoomOut
    QPoint m_mouseAnchor;
    QPoint m_mouseCurrent;
    graphics_handle m_mouseAxes;
    int m_eventMask;
    bool m_rectMode;
  };

}

#endif
